Ep 3. Parity

Sydney Bristow, a CIA agent who is also a double agent for a secretive organization known as SD-6, is tasked with stealing a mysterious document from a Russian embassy in Lisbon. To do so, she must pose as a wealthy art collector named Sasha Ivanov. However, things quickly become complicated when the embassy is attacked by a group of armed men and a security guard ends up getting killed in the crossfire.

Meanwhile, Sydney's friend and CIA handler, Michael Vaughn, meets with Jack Bristow, Sydney's father and a high-ranking SD-6 official. Vaughn tells Jack that the CIA has evidence that SD-6 is actually a branch of the Alliance of Twelve, a shadowy group that seeks to control the world through various means. He urges Jack to give him information that could help bring down SD-6 and the Alliance, but Jack is hesitant, citing concerns for his daughter's safety.

Back in Lisbon, Sydney manages to steal the document, but ends up getting caught by the embassy's head of security. To make matters worse, she runs into Anna Espinosa, a Russian agent who knows her true identity and is eager to kill her. Sydney is able to escape with the help of her SD-6 colleague, Marcus Dixon, but not before Anna injures her.

Back in Los Angeles, Sydney is debriefed by SD-6 leader Arvin Sloane, who tells her that the document she stole was part of a hidden cache of Rambaldi artifacts, which are said to hold immense power. He orders her to retrieve the rest of the artifacts as soon as possible, and warns her that failure to do so could result in dire consequences.

As Sydney struggles to deal with the aftermath of her mission, she also begins to suspect that her roommate, Will Tippin, may be investigating her activities for a newspaper article. She confronts him about it, but he denies it and puts the blame on his editor, who he says is forcing him to dig up dirt on the CIA.

In the episode's final scenes, Sydney meets with Vaughn in a park and tells him that she's willing to help the CIA take down SD-6. Vaughn is thrilled to hear this and tells her that he'll be in touch soon with more information. As Sydney walks away, she receives a phone call from her estranged mother, who tells her that she needs to come to Hong Kong right away. Sydney is reluctant, but her mother insists that it's a matter of life and death.